xor.diff

diff --git a/src/vm/moar/QAST/QASTOperationsMAST.nqp b/src/vm/moar/QAST/QASTOperationsMAST.nqp
index 5f53311..fd2f934 100644
--- a/src/vm/moar/QAST/QASTOperationsMAST.nqp
+++ b/src/vm/moar/QAST/QASTOperationsMAST.nqp
@@ -784,6 +784,84 @@ QAST::MASTOperations.add_core_op('defor', -> $qastcomp, $op {
     $expr
 });
 
+sub say_line(@ops, $n) {
+    my $sreg := $*REGALLOC.fresh_s();
+    push_op(@ops, 'const_s', $sreg, MAST::SVal.new( :value($n) ));
+    push_op(@ops, 'say', $sreg);
+}
+
+QAST::MASTOperations.add_core_op('xor', -> $qastcomp, $op {
+    my @ops;
+    my $res_kind   := $MVM_reg_obj;
+    my $res_reg    := $*REGALLOC.fresh_register($res_kind);
+    my $falselabel := MAST::Label.new(:name('xor_false'));
+    my $endlabel   := MAST::Label.new(:name('xor_end'));
+
+    my @comp_ops;
+    my $fpast;
+    for $op.list {
+        if $_.named eq 'false' {
+            $fpast := $qastcomp.as_mast($_);
+        }
+        else {
+            nqp::push(@comp_ops, $qastcomp.as_mast($_));
+        }
+    }
+
+    my $t := $*REGALLOC.fresh_i();
+    my $u := $*REGALLOC.fresh_i();
+
+    my $apast := nqp::shift(@comp_ops);
+    my $apost := $qastcomp.coerce($apast, $MVM_reg_obj);
+    push_ilist(@ops, $apost);
+    push_op(@ops, 'set', $res_reg, $apost.result_reg);
+    push_op(@ops, 'istrue', $t, $apost.result_reg);
+
+    my $have_middle_child := 1;
+    my $bpost;
+    while $have_middle_child {
+        my $bpast := nqp::shift(@comp_ops);
+        my $jumplabel := MAST::Label.new(:name('xor_jump'));
+        $bpost := $qastcomp.coerce($bpast, $MVM_reg_obj);
+        push_ilist(@ops, $bpost);
+        push_op(@ops, 'istrue', $u, $bpost.result_reg);
+
+        push_op(@ops, 'unless_i', $t, $jumplabel);
+        push_op(@ops, 'unless_i', $u, $jumplabel);
+        push_op(@ops, 'goto', $falselabel);
+        nqp::push(@ops, $jumplabel);
+
+
+        if @comp_ops {
+            my $truelabel := MAST::Label.new(:name('xor_true'));
+            push_op(@ops, 'if_i', $t, $truelabel);
+            push_op(@ops, 'set', $res_reg, $bpost.result_reg);
+            push_op(@ops, 'set', $t, $u.result_reg);
+            nqp::push(@ops, $truelabel);
+        }
+        else {
+            $have_middle_child := 0;
+        }
+    }
+
+    push_op(@ops, 'if_i', $t, $endlabel);
+    push_op(@ops, 'set', $res_reg, $bpost.result_reg);
+    push_op(@ops, 'goto', $endlabel);
+    nqp::push(@ops, $falselabel);
+
+    if $fpast {
+        my $fpost := $qastcomp.coerce($fpast, $res_kind);
+        push_ilist(@ops, $fpost);
+        push_op(@ops, 'set', $res_reg, $fpost.result_reg);
+    }
+    else {
+        push_op(@ops, 'null', $res_reg);
+    }
+
+    nqp::push(@ops, $endlabel);
+
+    MAST::InstructionList.new(@ops, $res_reg, $res_kind)
+});
+
 QAST::MASTOperations.add_core_op('ifnull', -> $qastcomp, $op {
     if +$op.list != 2 {
         nqp::die("The 'ifnull' op expects two children");
diff --git a/src/vm/parrot/pmc/qrpa.pmc b/src/vm/parrot/pmc/qrpa.pmc
index ded6173..7051b7c 100644
--- a/src/vm/parrot/pmc/qrpa.pmc
+++ b/src/vm/parrot/pmc/qrpa.pmc
@@ -171,7 +171,10 @@ Resizes the array to C<n> elements.
             Parrot_ex_throw_from_c_args(INTERP, NULL, EXCEPTION_OUT_OF_BOUNDS,
                     "QRPA: Can't resize to negative elements");
 
-        if (n == elems) { return; }
+        if (n == elems) {
+            PObj_custom_mark_destroy_SETALL(SELF);
+            return;
+        }
 
         /* if there aren't enough slots at the end, shift off empty slots 
          * from the beginning first */
@@ -189,6 +192,7 @@ Resizes the array to C<n> elements.
         qrpa->elems = n;
         if (n <= ssize) { 
             /* we already have n slots available, we can just return */
+            PObj_custom_mark_destroy_SETALL(SELF);
             return;
         }